Suppose x = 1.1, a = 2.2, and b = 3.3. Assign each expression to the value of the variable z and print the value stored in z.
x <- 1.1
a <- 2.2
b <- 3.3
z<-(x^(a^b))
print(z)
## [1] 3.61714
z<-(x^a)^b
print(z)
## [1] 1.997611
z<-(3*x^3)+(2*x^2) + 1
print(z)
## [1] 7.413
Using the rep and seq functions, create the following vectors:
(1,2,3,4,5,6,7,8,7,6,5,4,3,2,1)
a<-seq(from =1, to = 8)
b<-seq(from = 7, to =1)
z<-c(a,b)
print(z)
## [1] 1 2 3 4 5 6 7 8 7 6 5 4 3 2 1
(1,2,2,3,3,3,4,4,4,4,5,5,5,5,5)
a<-seq(from=1, to= 5)
z<-rep(a, time=a)
print(z)
## [1] 1 2 2 3 3 3 4 4 4 4 5 5 5 5 5
(5,4,4,3,3,3,2,2,2,2,1,1,1,1,1)
a<-seq(from=1, to= 5)
b<-rev(a)
z<-rep(b, time=a)
print(z)
## [1] 5 4 4 3 3 3 2 2 2 2 1 1 1 1 1
Create a vector of two random uniform numbers. In a spatial map,
these can be interpreted as x and y coordinates that give the location
of an individual (such as a marked forest tree in a plot that has been
mapped). Using one of R’s inverse trigonometry functions
(asin(), acos(), or atan())
, convert these numbers into
polar coordinates (If you don’t know what polar coordinates are, read
about them on the web here, here, or in your calculus textbook).
x<-100
y<-2500
theta<-atan2(x, y)
r<-sqrt((x^2)+(y^2))
Polar<-c(r, theta)
print(Polar)
## [1] 2.501999e+03 3.997869e-02
Create a vector
queue <- c("sheep", "fox", "owl", "ant")
where queue
represents the animals that are lined up to enter Noah’s Ark, with the
sheep at the front of the line. Using R expressions, update queue
as:
the serpent arrives and gets in line;
the sheep enters the ark;
the donkey arrives and talks his way to the front of the line;
the serpent gets impatient and leaves;
the owl gets bored and leaves;
the aphid arrives and the ant invites him to cut in line.
Finally, determine the position of the aphid in the line.
queue <- c("sheep", "fox", "owl", "ant")
print(queue)
## [1] "sheep" "fox" "owl" "ant"
queue<-c(queue, "serpent")
print(queue)
## [1] "sheep" "fox" "owl" "ant" "serpent"
queue<-c(queue[2:5])
print(queue)
## [1] "fox" "owl" "ant" "serpent"
queue<-c("donkey", queue)
print(queue)
## [1] "donkey" "fox" "owl" "ant" "serpent"
queue<-c(queue[1:4])
print(queue)
## [1] "donkey" "fox" "owl" "ant"
queue<-c(queue[1:2], queue[4])
print(queue)
## [1] "donkey" "fox" "ant"
queue<-c(queue[1:2], "aphid",queue[3])
print(queue)
## [1] "donkey" "fox" "aphid" "ant"
print(which("aphid" == queue))
## [1] 3
Use R to create a vector of all of the integers from 1 to 100 that are not divisible by 2, 3, or 7. You will need one of the arithmetic operators on this cheat sheet.
a<-1:100
b<- which(a%%2!=0 & a%%3!=0 & a%%7!=0)
print(b)
## [1] 1 5 11 13 17 19 23 25 29 31 37 41 43 47 53 55 59 61 65 67 71 73 79 83 85
## [26] 89 95 97